1. Field of the Invention
The present invention relates to a motor-driven lock, and particularly to a horizontal motor-driven lock having a simple transmission device. The instant invention relates to a copending application filed on Mar. 26, 2002, with an unknown serial number and the same applicant, titled as xe2x80x9cMOTOR-DRIVEN LOCKxe2x80x9d.
2. Prior Art
FIG. 1 shows an exploded view of a conventional lock 20 for a door in a building. The lock 20 includes an external controller 34, a latch subassembly (not shown), and an internal controller 22. An inside shaft 30 and an outside shaft 32 receiving the inside shaft 30 extend through the latch subassembly, and connect the external controller 34 and the internal controller 22. The latch subassembly is received in an opening (not shown) defined in a door (not shown), and projects sidewardly to be received in a recess (not shown) defined in a frame (not shown) of the door. The external controller 34 located at the outside of the door defines a first axial hole (not shown), for receiving the outside and inside shafts 30, 32. The internal controller 22 locating at the inside of the door defines a second axial hole 220, for receiving the outside and inside shafts 30, 32.
The internal controller 22 includes a manual switch 221 connecting the inside shaft 30, and a control shaft 222 connecting the outside shaft 32. The manual switch 221 is rotatable to rotate the inside shaft 30 to actuate a pin (not shown). The pin engages with or disengages from the outside shaft 32, thereby locking or unlocking the lock 20. Thus, the manual switch 221 controls the lock 20 being locked or unlocked via the inside shaft 30 controlling the outside shaft 32. The internal controller 22 rotates the control shaft 222 to control the outside shaft 32 to unlock the lock 20. A key (not shown) is receivable in the external controller 34, to control the outside shaft 32 to unlock the lock 20.
However, using a key to unlock a door lock can be inconvenient, particularly at night or when one""s hands are not free. A motor-driven lock can be more convenient. Even then, transmission devices of conventional motor-driven locks are complicated. Furthermore, a conventional lock is configured such that it can only be fitted to a left side or a right side of a door. Thus two configurations of a conventional lock are needed to meet the differing requirements of all kinds of doors. This unduly inflates costs. U.S. Pat. Nos. 3,767,240, 4,438,962, 4,483,162, 5,790,034, 5,857,365, 5,979,199, 6,012,310 and 6,032,991 disclose some examples.
Accordingly, an object of the present invention is to provide a motor-driven lock having a simple transmission device for easy manufacturing and reduced costs.
Another object of the present invention is to provide a motor-driven lock having a transmission device that allows the lock to be fitted to a left side or a right side of a door.
To achieve the above-mentioned objects, a motor-driven lock of the present invention includes a housing defining a central hole, a lock body extending through the central hole of the housing and attached to the housing, a motor received in the housing and having a motor gear, a transmission device received in the housing and mating with the motor and the lock body, a lid attached to the housing over the transmission device, an enclosure attached to one side of the housing, and a cover attached to another side of the housing. The lock body includes a controller having a gear portion, a cap attached to the controller, and a handle extending through the cap and attached to the controller. The transmission device includes a first gearshaft meshed with the motor gear of the motor, a second gearshaft meshed with the first gearshaft, a wheel meshed with the second gearshaft, a screw shaft fixing the wheel thereon, a slider mating with the screw shaft, a yoke slidingly movable along the housing and actuatable by the slider, and a gear set. The gear set is attached to the cap of the lock body, meshed with the gear portion of the lock body, and mated with either of two racks of the yoke.
Other objects, advantages and novel features of the present invention will be drawn from the following detailed description of a preferred embodiment of the present invention with attached drawings, in which: